The
Advanced Passenger Train (
APT) was an experimental
tilting high speed train developed by
British Rail during the 1970s and early 1980s, for use on the
West Coast Main Line, which contained a lot of curves. Notable among numerous technical advancements was the active tilting system, which the APT pioneered and has since appeared on other designs around the world. Other features of the APT such as the
hydrokinetic braking, used to stop the train within existing separations, have not been adopted. The experimental version
APT-E achieved a new British railway speed record when on 10 August 1975 it hit 152.3 mph (245.1 km/h).